Switch mechanism



Jan; 31, 1928. 1,657,714

T. E. GRIFFITH ET AL SWITCH MECHANISM Filed March 5, 1925 HAIR I 4 \&

INVENTORS. Thomas [.Griffith Y BY Lee L. Dodds A TTORNEYS.

Patented Jan. 31, 1928.

UNITED STATES PATENT OFFICE.

THOMAS E. GRIFFI ETH AND LEE L. DODDS, OF

CLEVELAND, OHIO, ASSIGNOBS TO THE W. S. TYLER COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO.

SWITCH nnonenrsn.

Application filed March 5, 1923. Serial No. 623,056.

The present invention, relating to switch mechanism, is more particularly directed to an improved switch for use in elevator cars for breaking the operating circuit of the car upon theopening of the door of the elevator enclosure. One of the important purposes of the present mechanism is to provide a switch which will open quickly and positive ly, and eliminate, so far as possible, all arcing. To the accomplishment of theforegoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claim.

The annexed drawing and the following description set forth in detail certain mechanism embodying the invention, such disclosed means constituting, however, but one of various mechanical forms in which the principle of the invention may be used.

In said annexed drawing Fig. 1 is an elevation looking from the interior of an elevator car of the enclosure and doors therefor, and showing the mounting of the present switch mechanism; Fig. 2 is a vertical longitudinal section through the switch mechanism showing the construction thereof in one position; Fig. 3 is a similar View showing the switch member in a second position; and Fig. 4 is a section on the line k4, in Fig. 3. g

In Fig. 1 there is shown an elevator enclosure 1 provided with a door 2 and a look ing mechanism in the form of a. reciprocable rod 4, provided with a cam-shaped head 5 which engages against a stop 6 on the enclosure to retain the doorin closed position.

At the top of the enclosure is mounted a switch casing 7 enclosing the present switch mechanism, which is actuated by means of a projection or lug 8 carried by the carriage mechanism 9 which supports the door 2. This switch mechanism consists of an external operating member 10, which is provided with a slot 11, into which projects the operating lug 8 on the carriage 9 so that the movement of the door will cause the lug to engage, first against the side 12 of the slot 10 in the opening movement thereof, and then against the side 13 when closing, and swing the member 10, and also the shaft 14, to which it is attached; The switch mechanism proper consists of a switch element 15 of insulating material, which is rotatably mounted on the shaft 14, and is actuated by means of an arm 16, which is fixed to said shaft. This operation is by means of aslot 17 formed in the member 16, into which extends a pin 18 carried on the member 15. At its outer end the switch element 15 is provided with a metal strip 19 extending across one face and down two sides thereof, and engaging, in the position of the switch shown in F ig. 2, with spring switch elements 20 and 21, which are provided with binding screws 23 and 24, respectively, for attaching electrical conducting connections 25 and 26, which extend out of the casing through openings 27 and 28, and are there connected with the operating circuit for the motors of the elevator.

The operation of the switch mechanism is as follows :When the door 2 is opened and is moved to the left with the carriage 9, the lug 8 on the latter moves to the left side of the slot 11, and engages against the face or projection 12. Further movement of the door turns the shaft 14 in a clockwise direction and causes the member 16 to be moved with the shaft, and after a certain amount of movement the right side of the slot 17 en gages a pin 18 and pulls the switch member 15 from its engagement between the spring fingers 20 and 21. Further movement of the switch member 15 is by gravity. and upon return of the door, the switch member, which is in a vertical position, is not again brought into contact with the spring fingers 20 and 21 until the door is almost closed, when the left side of the slot 17 picks up the pin 18 and snaps the switch shut very quick- 1y. The lost motion in the operating connections between the door-and the switch member proper permits an extremely rapid opening and closing of the switch, and the result is a minimum of arcing. A further advantage is that this lost motion insures that the switch is opened as soon as the enclosure door has opened a predetermined distance, but is not closed until the final travel of the door, so that as long as the door is open the operating circuit for the car motors is disconnected, and the car cannot be started until the door is entirely shut.

We therefore particularly point out and distinctly claim as our invention In elevator switch mechanism, the combination of a sliding door, a vertically projecting lug mounted thereon, a pivoted arm mounted above said lug and provided in its under side with spaced stops for receiving said lug therebetween, said stops providing lost motion during the opening movement of thedoor, a second pivoted arm actuated by I? said first arm and having a slot therein, two

apivotedswitch member of said second pivot arm and normally hanging out of engagement with said contacts, and a pin projecting from spaced contacts, mounted axially said switch member and engaging in such 10 slot whereby movement of said arms causes a delayed movement of said'switch member in the opening of the door.

Signed by'us, this 20th'day of February, 1923. I

THOMAS E. GRIFFITH. LEE LIDODDS. 

